Checking The Refrigerant Piping; Checking Refrigerant Piping: Setup; To Check For Leaks; To Perform Vacuum Drying - Daikin RZAG71M7V1B Installation Manual

4 Installation
NOTICE
Do not block the air vents. This could affect air circulation
inside the unit.
WARNING
Provide adequate measures to prevent that the unit can be
used as a shelter by small animals. Small animals that
make contact with electrical parts can cause malfunctions,
smoke or fire.
NOTICE
Make sure to open the stop valves after installing the
refrigerant piping and performing vacuum drying. Running
the system with the stop valves closed may break the
compressor.
4.3

Checking the refrigerant piping

4.3.1

Checking refrigerant piping: Setup

a
A
c
R32
b d e
a
B
c
R32
b d e
A Setup in case of pair
B Setup in case of twin
a Pressure gauge
b Nitrogen
c Refrigerant
d Weighing machine
e Vacuum pump
f Stop valve
g Main piping
h Refrigerant branch kit
i Branch piping
4.3.2

To check for leaks

NOTICE
Do NOT exceed the unit's maximum working pressure (see
"PS High" on the unit name plate).
Installation manual
8
f
f
i
g
h
NOTICE
Make sure to use a recommended bubble test solution
from your wholesaler. Do not use soap water, which may
cause cracking of flare nuts (soap water may contain salt,
which absorbs moisture that will freeze when the piping
gets cold), and/or lead to corrosion of flared joints (soap
water may contain ammonia which causes a corrosive
effect between the brass flare nut and the copper flare).
1 Charge the system with nitrogen gas up to a gauge pressure of
at least 200 kPa (2 bar). It is recommended to pressurize to
3000 kPa (30 bar) in order to detect small leaks.
2 Check for leaks by applying the bubble test solution to all
connections.
3 Discharge all nitrogen gas.
4.3.3

To perform vacuum drying

NOTICE
▪ Connect the vacuum pump to both the service port of
the gas stop valve and the service port of the liquid
stop valve to increase efficiency.
▪ Make sure that the gas stop valve and liquid stop valve
are firmly closed before performing the leak test or
vacuum drying.
1 Vacuum the system until the pressure on the manifold indicates
−0.1 MPa (−1 bar).
2 Leave as is for 4-5 minutes and check the pressure:
If the pressure...
Does not change
Increases
3 Evacuate for at least 2 hours to a pressure on the manifold of
−0.1 MPa (−1 bar).
4 After turning OFF the pump, check the pressure for at least
1 hour.
5 If you do NOT reach the target vacuum or cannot maintain the
vacuum for 1 hour, do the following:
▪ Check for leaks again.
▪ Perform vacuum drying again.
NOTICE
Make sure to open the stop valves after installing the
refrigerant piping and performing vacuum drying. Running
the system with the stop valves closed may break the
compressor.
4.4

Charging refrigerant

4.4.1

About charging refrigerant

The outdoor unit is factory charged with refrigerant, but in some
cases the following might be necessary:
What
Charging additional refrigerant
Completely recharging refrigerant Example:
Then...
There is no moisture in the
system. This procedure is
finished.
There is moisture in the
system. Go to the next step.
When
When the total liquid piping
length is more than specified
(see later).
▪ When relocating the system.
▪ After a leak.
RZAG71~140M_V1+Y1
Sky Air Alpha-series
4P485927-1 – 2017.04